MECHANISM
OF ACTION

RYSTIGGO is a humanized monoclonal
antibody designed to block FcRn
in adults with anti-AChR Ab+ or
anti-MuSK Ab+ gMG1,2*

The precise mechanism through which RYSTIGGO exerts therapeutic effects in gMG is unknown.

RYSTIGGO is a humanized monoclonal antibody designed to block FcRn in adults with anti-AChR Ab+ or anti-MuSK Ab+ gMG1,2*

The precise mechanism through which RYSTIGGO exerts therapeutic effects in gMG is unknown.

RYSTIGGO is engineered to block FcRn1

RYSTIGGO is an immunomodulatory agent, specifically targeting FcRn to reduce IgG levels with no effect on other antibodies.1,3,4

FcRn is a receptor expressed on the endothelial cells that mediates a natural salvage and recycling mechanism. IgG antibodies bound to FcRn are returned to circulation and escape lysosomal degradation.5

Mechanism of Action

High-affinity and high-avidity binding

RYSTIGGO binds to FcRn with high affinity and high avidity, reducing IgG recycling and leading to degradation.1,3,6†

Clinical data with RYSTIGGO have not identified any clinically relevant impact on levels of albumin, which binds at a different site on FcRn.3,6

RYSTIGGO has high specificity for FcRn with no cross-reactive protein or tissue binding.3

Mechanism of Action

Learn more about the pharmacodynamic effects of
RYSTIGGO in the IgG data section

VIEW IgG DATA

 

Discover how RYSTIGGO works

Learn more about how blocking FcRn removes AChR and MuSK autoantibodies.1

Press play to watch the full video or select a chapter that interests you:

RYSTIGGO Indication

gMG MOD

AChR and MuSK Autoantibodies

Antibody Recycling in gMG

RYSTIGGO MOA

Important Safety Information

Based on in vitro data.4  

Ab+=antibody positive; AChR=acetylcholine receptor; FcRn=neonatal Fc receptor; gMG=generalized myasthenia gravis; IgG=immunoglobulin G; MuSK=muscle-specific tyrosine kinase.

References:

  1. RYSTIGGO [Prescribing Information]. Smyrna, GA: UCB, Inc.
  2. Lledo-Garcia R, Dixon K, Shock A, et al. Pharmacokinetic-pharmacodynamic modelling of the anti-FcRn monoclonal antibody rozanolixizumab: translation from preclinical stages to the clinic. CPT Pharmacometrics Syst Pharmacol. 2022;11(1):116-128. doi:10.1002/psp4.12739
  3. Smith B, Kiessling A, Lledo-Garcia R, et al. Generation and characterization of a high affinity anti-human FcRn antibody, rozanolixizumab, and the effects of different molecular formats on the reduction of plasma IgG concentration. MAbs. 2018;10(7):1111-1130. doi:10.1080/19420862.2018.1505464
  4. Yang CW, Xia T, Tan Q, et al. From promise to practice: evaluating the clinical impact of FcRn inhibition in IgG-mediated autoimmune rheumatic diseases. Front Immunol. 2025;16:1-20. doi:10.3389/fimmu.2025.1656937
  5. Gable KL, Guptill JT. Antagonism of the neonatal Fc receptor as an emerging treatment for myasthenia gravis. Front Immunol. 2020;10(3052):1-9. doi:10.3389/fimmu.2019.03052
  6. Bril V, Drużdż A, Grosskreutz J, et al. Safety and efficacy of rozanolixizumab in patients with generalised myasthenia gravis (MycarinG): a randomised, double-blind, placebo-controlled, adaptive phase 3 study. Lancet Neurol. 2023;22(5):383-394. doi:10.1016/S1474-4422(23)00077-7